1. Field of the Invention
The invention relates to a soccer practice ball and, more particularly, to a kick-strengthening soccer practice ball as well as. its production and methods of training with it.
Briefly stated, the inventive practice ball optionally weighs something more than a regulation game ball, but not nearly so much more as seen in prior art medicine balls. Those are too heavy, and are unsafe for kicking. Also, the inventive practice ball preferably has a shock-absorbing softness to it. That way, the softer impact felt during kicking practice likely eliminates repetitive stress injuries. Weighting the ball while softening it too can be achieved together by any of (i) replacing the prior art padding layer (if any) with a thicker layer, (ii) placing additional padding underneath the carcass knowing that the inflating the bladder will compress such padding into the carcass, or (iii) using heavier carcass material.
In most other respects, the inventive practice ball is produced for otherwise closely resembling a regulation xe2x80x9cgamexe2x80x9d ball of applicable international standards. It has virtually the same circumference, and takes virtually the same inflation pressure(s).
2. Prior Art
The standard measure of a xe2x80x9cgamexe2x80x9d ball for soccer has been established under the authority of an international federation, or FIFA. That standard recites some of the following. The soccer ball shall be spherical. The outer casing shall be leather:xe2x80x94however, there is some admittance for other approved materials. The circumference of the ball shall not be more than 28 inches (71 cm) and not less than 27 inches (68-xc2xd cm). The weight of the ball at the start of a game shall not be more than 16 ounces (396 grams) or less than 14 ounces (453 grams). The inflation pressure shall be between 0.6 and 1.1 atmospheres (600 and 1,100 millibar) at sea level. Although, nowadays it is far more typical to maintain the ball pressure in an official match within a narrower band, say, between about 0.9 and 1.1 atmospheres. See, eg., the International Matchball Standards of the FIFA.
Regulation game balls are available off-the-shelf from numerous commercial sources. There is a surprising variety in the construction of these game balls. Yet there are several shared aspects which consistently appear in the game balls known to date. These include the following. The carcass is typically constructed from panels. Some designs have thirty-two (32) panels, others have eighteen (18), and still others have just eight (8). The thirty-two (32) panel variety is the one most familiar to the inventor hereof. Hence the thirty-two (32) panel soccer ball evidently comprising about twelve (12) pentagonal panels evenly mixed among twenty (20) hexagonal panels, arranged along each one""s edges and sewn together to form seams to give the approximate overall xe2x80x9csphericalxe2x80x9d shape. The panels are generally produced from leather, although other synthetic materials are common nowadays. The eight and eighteen (8 and 18) panel soccer balls are likewise produced by panels meeting at seams, irrespective of the differing geometries for the panels. Hence what is so commonly referred to as the xe2x80x9ccarcassxe2x80x9d is in fact a pieced-together construct of panels.
Inflation is sustained by a bladder. A typical bladder comprises a natural or synthetic rubber (eg., butyl rubber), or admixture (eg., 20% natural and 80% butyl rubber), having a uniform wall thickness and inflatable into a spherical shape.
The bladder and carcass aside, there is typically at least one other component:xe2x80x94ie., something that serves to constrain expansion of the bladder from expansion beyond a given measured, circumferential limit. Many materials have been used in service of expansion constraint. In U.S. Pat. No. 5,681,233xe2x80x94Guenther et al., the basketball disclosed thereby of Wilson Sporting Goods Co. has a winding for constraining the bladder from over-expansion. The winding comprises about 2100 meters of 210 denier Nylon 66 thread. In U.S. Pat. No. 4,462,590xe2x88x92Mitchell, the football disclosed thereby of Figgie International Corp. has a sheath around the bladder for restraining expansion of the bladder when inflated. As recited therein,
. . . When the ball is inflated to its full playing pressure, the sheath should be strong enough to contain a relatively large percentage (but not all) of the pressure forces, so that the net force exerted against the carcass is only about 1-5 psi [eg., wherein full playing pressure for a football is about 13 psi]. It is necessary that at least some force be exerted against the carcass to maintain it taut. It has been found that polyurethane film sold by Tetra Plastics Inc. of St. Louis, Mo. under the designation TP400 has the requisite properties for sheath material. This film has a thickness of about 0.018 in. (0.046 cm.) . . . .
. . . [In use,] the bladder may then be inflated to expand and stretch the sheath until it substantially conforms to the inside walls of the carcass. As noted hereinabove, the material out of which the sheath 19 is made is sufficiently strong that the force exerted against the inside of the carcass is relatively small (eg., 1-5 psi in the case of a football) so as not to subject the carcass to excessive internal pressures which would otherwise tend to cause the carcass to lose its shape relatively quickly. Column 3, lines 3-13, and column 4, lines 46-55.
Another sheath-type of construction used in soccer balls is to apply woven material directly as a backing to each individual leather panel. Hence the carcass of such a ball comprises a dual-layer carcass, ie., an outer leather layer and an inner woven-sheath backing. An inflatable bladder is incorporated as customary to xe2x80x9cfloatxe2x80x9d (not be attached) inside the carcass, its inflation pressure and nipple tending to stabilize the bladder in position. In the majority of cases, the sheath layersxe2x80x94while relatively rigid when stretched tight by an inflated bladderxe2x80x94also are collapsible under deflation to permit compaction for shipping and bulk handling purposes.
The U.S. Pat. No. 5,286,020 of Caruso, discloses a heavy, 32 ounce (2 lbs or 0.9 kg) medicine ball for soccer practice. The Caruso medicine ball is unsuitable for kick-strengthening purposes, and neither the patent nor the inventor""s commercial literature makes and dispute about that. With reference to the patent, it discloses preferred ranges of dimensions for construction of the Caruso medicine ball. This medicine ball is available on the market and, in the commercial literature for it, the Caruso medicine on is listed at weighing 2 lbs (0.9 kg). It also inflated to just a low pressure. More particularly,
When it is used, the medicine ball is inflated to a low pressure such as 2-10 psi, expanding the bladder so that it will lightly contact the inside cover 14. At such low pressures the ball is softer, more pliable and more deformable than standard inflatable sport balls, and the ball has a lower coefficient of elastic resolution than conventional sport balls. Because the walls of the bladder 18 are thick and the inflation pressure low, the ball can be grasped easily even by a small child. Because it is pliable, the ball cannot be bounced, and should not be kicked or headed . . . .
. . . It has a sturdy leather or plastic cover and inflatable inner bladder of sufficient thickness that, at relatively low inflation pressures, permits the ball to be lighter in weight than conventional medicine balls yet pliable so that it easy to throw or catch, even for children. The lighter ball is less likely to cause injuries [than standard lead-weighed medicine balls], but as with standard medicine balls should not be kicked or headed like a soccer ball. Column 2, line 59, continuing into column 3, line 1, and column 1, lines 41-53.
These warnings regarding xe2x80x9cNOT TO BE USED FOR KICKING OR HEADINGxe2x80x9d are repeated as stated in both the commercial literature and directly applied onto the Caruso medicine ball, selling under the Kwik Goal Ltd. (Quakerstown, Pa.) brand name.
What is needed is an improvement which overcomes the shortcomings of the prior art for kick-strengthening training for soccer athletes.
It is an object of the invention to provide a kick-strengthening soccer practice ball.
It is an additional object of the invention to arrange the above practice ball so that it weighs slightly more than a regulation game ball, but is inflated to about the same pressures to yield a comparable xe2x80x9ccoefficient of elastic resolutionxe2x80x9d as a regulation ball. However, preferably the target xe2x80x9ccoefficient of elastic resolutionxe2x80x9d is indeed just slightly lessened by incorporation of a shock-absorbing layer beneath the carcass. Such a shock-absorbing layer shall spread the forces of kicking-impact over a minutely bigger time span to lessen the stress felt by a trainee while kicking the practice ball.
It is an alternate object of the invention to convert a regulation soccer ball into the inventive practice ball by inserting extra under the carcass, and hence add between about 2 and 10 ounces (56 and 280 grams) of increased weight.
It is a further object of the invention to produce the practice ball in a set, each ball of such a set having a progressively different weight. Hence kick-strengthening training occurs with progressively heavier or lighter ballsxe2x80x94much like how an athlete in weight training resorts to a dumbbell rack with different weight gradations among dumbbells. The gradations may occur in 2 ounce (56 gram) steps or so, between the preferred extremes of 2 and 10 ounces (56 and 280 grams) of increased weight.
These and other aspects and objects are provided according to the invention in a kick-strengthening soccer practice ball. One version of the invention is achieved by converting a regulation game ball into a practice ball in accordance with the invention by symmetrically distributing a patchwork of padding material as a backing material onto some or all of the leather panels of the carcass. It is preferred if between about 2 and 10 ounces (56 and 280 grams) of increased weight is added thereby.
Optionally the inventive practice ball can be produced in a set, each ball of such a set having a progressively different weight. Hence kick-strengthening training occurs with progressively heavier or lighter ballsxe2x80x94much like how an athlete in weight training resorts to a dumbbell rack with different weight gradations among dumbbells. The gradations may occur in 2 ounce (56 gram) steps or so, between the preferred extremes of 2 and 10 ounces (56 and 280 grams) of increased weight.
A number of additional features and objects will be apparent in connection with the following discussion of preferred embodiments and examples.